Here is a part of CVC 22400. Please remember that 22400(a) never says you cannot stop in a highway ramp. Yes you can. It is only a violation of 22400(a) if you blocked the reasonable flow of the traffic. If there was no car behind yours or no car was blocked trying to get on the highway then you would have an argument. It is not a violation either if you must stop for safety reasons or directed by the police, which obviously does not appply to your situation.
No person shall bring a vehicle to a complete stop upon a highway so as to impede or block the normal and reasonable movement of traffic unless the stop is necessary for safe operation or in compliance with law.
